How do you contact nationwide insurance? Nationwide Insurance Headquarters Phone Number. Customer Service Support Phone Number: 1-877-669-6877. The number given above may not be a toll free phone number and you may get charged while calling this number at the usual calling prices.What is the toll free number for nationwide insurance? The official mailing/postal address, payment office, Headquarters and location address of Nationwide Insurance is given below. People can use this contact details to contact them and get their concern or query answered quickly. Nationwide Insurance Headquarters Phone Number Toll Free: 1-614-249-7111.How can i contact nationwide? Contacting Nationwide Insurance. Nationwide Insurance does not provide customer service by email, but does provide it by phone. There are 4 ways to reach Nationwide Insurance across 2 communication modes: phone, web. In case you didn't realize there was an alternative, the best phone number for Nationwide Insurance customer support is 800-421-3535.